Communication terminal, communication system, communication method, and recording medium

ABSTRACT

A communication terminal receives, from a mobile terminal, first terminal identification information for identifying a first communication terminal that is located remotely from the communication terminal, the mobile terminal being a mobile terminal that has obtained the first terminal identification information from the first communication terminal, determines the first communication terminal identified with the first terminal identification information as a communication destination, and starts communicating with the first communication terminal.

CROSS-REFERENCE TO RELATED APPLICATIONS

This patent application is based on and claims priority pursuant to 35U.S.C. §119(a) to Japanese Patent Application Nos. 2015-073388, filed onMar. 31, 2015, and 2016-046204, filed on Mar. 9, 2016, in the JapanPatent Office, the entire disclosure of which is hereby incorporated byreference herein.

BACKGROUND

1. Technical Field

The present invention relates to a communication terminal, acommunication system including the communication terminal, acommunication method, and a non-transitory recording medium storing acommunication control program.

2. Description of the Related Art

Recently, videoconference systems are widely used. The videoconferencesystems transmit or receive image data and audio data among a pluralityof communication terminals such as videoconference terminals.

In order to start communication with a counterpart communicationterminal, a user at a communication terminal usually selects onecommunication terminal from among a plurality of communication terminalspreviously registered. This could be cumbersome and time-consuming,especially in case there are many of registered communication terminals.Further, in case a counterpart communication terminal has not beenregistered, the user has to manually enter a destination address, ornewly register the counterpart communication terminal, before startingcommunication.

SUMMARY

Example embodiments of the present invention include a communicationterminal to communicate with a counterpart communication terminal. Thecommunication terminal receives, from a mobile terminal, first terminalidentification information for identifying a first communicationterminal that is located remotely from the communication terminal, themobile terminal being a mobile terminal that has obtained the firstterminal identification information from the first communicationterminal, determines the first communication terminal identified withthe first terminal identification information as a communicationdestination, and starts communicating with the first communicationterminal.

Example embodiments of the present invention include a method performedby the communication terminal, a communication system including thecommunication terminal, and a non-transitory recording medium storing acontrol program for causing one or more processors to perform thecommunication method.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

A more complete appreciation of the disclosure and many of the attendantadvantages and features thereof can be readily obtained and understoodfrom the following detailed description with reference to theaccompanying drawings, wherein:

FIG. 1 is a schematic diagram illustrating a part of a communicationsystem relating to videoconference communication, according to anexample embodiment of the present invention;

FIG. 2 is a schematic block diagram illustrating a hardwareconfiguration of a communication terminal of the communication system ofFIG. 1;

FIG. 3 is a schematic block diagram illustrating a hardwareconfiguration of a communication management system and a relay device ofthe communication system of FIG. 1;

FIG. 4 is a schematic block diagram illustrating a hardwareconfiguration of an electronic whiteboard of the communication system ofFIG. 1;

FIG. 5 is a schematic block diagram illustrating a hardwareconfiguration of a mobile terminal of the communication system of FIG.1;

FIG. 6A is a schematic block diagram illustrating a softwareconfiguration of the communication terminal as the videoconferenceterminal according to the embodiment of the invention;

FIG. 6B is a schematic block diagram illustrating a softwareconfiguration of the communication terminal as the electronic whiteboardaccording to the embodiment of the present invention;

FIG. 7 is a schematic diagram illustrating a network configuration ofthe communication system of FIG. 1;

FIGS. 8A and 8B (FIG. 8) are a schematic block diagram illustrating afunctional configuration of the communication system of FIG. 1 accordingto the embodiment of the present invention;

FIG. 9 is an illustration of an example data structure of anauthentication management table;

FIG. 10 is an illustration of an example data structure of a terminalmanagement table;

FIG. 11 is an illustration of an example data structure of a contactlist management table;

FIG. 12 is an illustration of an example data structure of an additionrequest management table;

FIG. 13 is an illustration of an example data structure of anear-distance communication circuit;

FIG. 14 is a data sequence diagram illustrating operation of providingterminal identification information, performed by the communicationterminal of FIG. 1, according to an embodiment of the present invention;

FIG. 15 is an illustration of an example screen for display in providingthe terminal identification information;

FIGS. 16A and 16B (FIG. 16) are a data sequence diagram illustratingoperation of preparing for communication between the communicationterminals of the communication system of FIG. 1;

FIG. 17 is an illustration of an example contact list screen;

FIG. 18 is a data sequence diagram illustrating operation of providingterminal identification information, from the mobile terminal to thecommunication terminal of the communication system of FIG. 1, accordingto an embodiment of the present invention;

FIG. 19 is a flowchart illustrating operation of identifying adestination according to an embodiment of the present invention;

FIGS. 20A and 20B (FIG. 20) are a data sequence diagram illustratingoperation of adding a candidate counterpart terminal to a contact list,according to an embodiment of the present invention;

FIG. 21 is an illustration of an example screen for requesting approvalto add a candidate counterpart terminal to the contact list; and

FIG. 22 is a data sequence diagram illustrating operation of preparingfor transmission of image data and audio data between the communicationterminals of the communication system of FIG. 1.

The accompanying drawings are intended to depict example embodiments ofthe present invention and should not be interpreted to limit the scopethereof. The accompanying drawings are not to be considered as drawn toscale unless explicitly noted.

DETAILED DESCRIPTION

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the presentinvention. As used herein, the singular forms “a”, “an” and “the” areintended to include the plural forms as well, unless the context clearlyindicates otherwise. It will be further understood that the terms“includes” and/or “including”, when used in this specification, specifythe presence of stated features, integers, steps, operations, elements,and/or components, but do not preclude the presence or addition of oneor more other features, integers, steps, operations, elements,components, and/or groups thereof.

In describing example embodiments shown in the drawings, specificterminology is employed for the sake of clarity. However, the presentdisclosure is not intended to be limited to the specific terminology soselected and it is to be understood that each specific element includesall technical equivalents that operate in a similar manner.

Referring to the drawings, an embodiment of the present invention isdescribed.

<Configuration of Communication System>

Referring to FIG. 1, a communication system 1 for carrying outvideoconference among a plurality of communication terminals (10, 70) isdescribed according to the embodiment. FIG. 1 is a schematic diagramillustrating a portion of the communication system 1, which relates tovideoconference being carried out between the communication terminals 10and 70.

In the following, it is assumed that the communication system 1 managestransmission of content data to carry out videoconference among theterminals. Alternatively, the communication system 1 may managetransmission of content data to carry out casual conversation among theusers at different sites.

The communication system 1 includes the plurality of communicationterminals (10, 70), a relay device 30, and a communication managementsystem 50. The communication terminal transmits or receives image dataand audio data as an example of content data. In FIG. 1, thecommunication terminal may be implemented by a videoconference terminal10 in one example, or by en electronic whiteboard 70 in another example.The image data may be a video image or a still image, or both of thevideo image and the still image.

In this disclosure, the communication terminal that sends a request forstarting videoconference is referred to as the “starting terminal”, andthe communication terminal serving as a request destination (relaydestination) of videoconference is referred to as the “counterpartterminal”. In FIG. 1, the communication terminal 10 is referred to asthe starting terminal, and the communication terminal 70 is referred toas the counterpart terminal. Alternatively, when the communicationterminal 70 requests to start videoconference with the communicationterminal 10, the communication terminal 70 is referred to as thestarting terminal, and the communication terminal 10 is referred to asthe counterpart terminal. Note that the communication terminal may beused not only for communication between different offices or forcommunication between different rooms in the same office, but also forcommunication within the same room or for outdoor-indoor communicationor outdoor-outdoor communication.

The relay device 30 relays content data among the plurality ofcommunication terminals. The communication management system 50centrally controls login authentication of the communication terminal,management of the communication state of the communication terminal,management of a contact list, and management of the communication stateor the like of the relay device 30. The relay devices 30 and themanagement system 50 in the above-described embodiment may be configuredby a single computer or a plurality of computers to which dividedportions (functions) are arbitrarily allocated.

In the communication system 1, a management data session “sei” isestablished between the starting terminal 10 and the counterpartterminal 70 via the communication management system 50 to transmit orreceive various management data. Between the starting terminal 10 andthe counterpart terminal 70, four sessions are established via the relaydevice 30 to transmit or receive four items of data includinghigh-resolution image data, intermediate-resolution image data,low-resolution image data, and audio data. In FIG. 1, these foursessions are collectively referred to as image and audio data session“sed”. The image and audio data session “sed” may not always includefour sessions, but any number of sessions greater than or less thanfour. Any communication terminal (10 or 70) may communicate with eachother through directly establishing a session with each other withoutintervening the relay device 30.

Now, resolution of image data to be processed in this embodiment isdescribed. The low-resolution image data serves as a base image and hashorizontal 160 pixels by vertical 120 pixels. Theintermediate-resolution image data has horizontal 320 pixels by vertical240 pixels. The high-resolution image data has horizontal 640 pixels byvertical 480 pixels. In the case of a narrow band path, low-qualityimage data that only includes low-resolution image data serving as abase image is relayed. In the case of a relatively wide band path,intermediate-quality image data including low-resolution image dataserving as a base image and intermediate-resolution image data isrelayed. In the case of a very wide band path, high-quality image dataincluding low-resolution image data serving as a base image,intermediate-resolution image data, and high-resolution image data isrelayed. Since audio data is relatively small in data size, the audiodata is relayed even in the case of a narrow band path.

<Hardware Configuration of Communication System>

Now, a hardware configuration of the communication system 1 isdescribed.

<Hardware Configuration of Videoconference Terminal>

FIG. 2 illustrates a hardware configuration of the videoconferenceterminal according to the embodiment of the present invention. Asillustrated in FIG. 2, the videoconference terminal as an example of thecommunication terminal includes a central processing unit (CPU) 101, aread only memory (ROM) 102, a random access memory (RAM) 103, a flashmemory 104, a solid state drive (SSD) 105, a medium interface (I/F) 107,an operation key 108, a power switch 109, a bus line 110, a network I/F111, a camera 112, an imaging device I/F 113, a microphone 114, aspeaker 115, an audio input/output I/F 116, a display I/F 117, anexternal device connection I/F 118, a near-distance communicationcircuit 119, and an antenna 119 a for the near-distance communicationcircuit 119. The CPU 101 controls entire operation of the communicationterminal 10. The ROM 102 stores a control program for operating the CPU101 such as an Initial Program Loader (IPL). The RAM 103 is used as awork area for the CPU 101. The flash memory 104 stores various data suchas a communication control program, image data, and audio data. The SSD105 controls reading or writing of various data to or from the flashmemory 105 under control of the CPU 101. In alternative to the SSD, ahard disk drive (HDD) may be used. The medium I/F 107 controls readingor writing of data with respect to a recording medium 106 such as aflash memory. The operation key 108 is operated by a user to input auser instruction such as a user selection of a destination of thecommunication terminal 10. The power switch 109 turns on or off thepower of the communication terminal 10.

The network I/F 111 allows communication of data with an external devicethrough a communication network 2 such as the Internet. The camera 112is an example of imaging device capable of capturing a subject undercontrol of the CPU 101, and may be incorporated in the communicationterminal. The imaging element device I/F 113 is a circuit that controlsdriving of the camera 112. The microphone 114 is an example of audiocollecting device capable of inputting audio under control of the CPU101, and may be incorporated in the communication terminal. The audioI/O I/F 116 is a circuit for inputting or outputting an audio signalbetween the microphone 114 and the speaker 115 under control of the CPU101. The display I/F 117 is a circuit for transmitting image data to theexternal display 120 under control of the CPU 101. The external deviceconnection I/F 118 is an interface circuit that connects the terminal 10to various external devices. The near-distance communication circuit 119is a communication circuit in compliance with a near-field communication(NFC; Registered Trademark) or Bluetooth (Registered Trademark).

The bus line 110 may be an address bus or a data bus, which electricallyconnects various elements such as the CPU 101 of FIG. 2.

The display 120 may be a liquid crystal or organic electroluminescence(EL) display that displays an image of a subject, an operation icon, orthe like. The display 120 is connected to the display I/F 117 by thecable 120 c. The cable 120 c may be an analog red green blue (RGB)(video graphic array (VGA)) signal cable, a component video cable, ahigh-definition multimedia interface (HDMI) signal cable, or a digitalvideo interactive (DVI) signal cable.

The camera 112 includes a lens and a solid-state imaging element thatconverts an image (video) of a subject to electronic data by convertinglight to electric charge. As the solid-state imaging element, forexample, a complementary metal-oxide-semiconductor (CMOS) or acharge-coupled device (CCD) is used. The external device connection I/F118 is capable of connecting an external device such as an externalcamera, an external microphone, or an external speaker through aUniversal Serial Bus (USB) cable or the like. In the case where anexternal camera is connected, the external camera is driven inpreference to the built-in camera 112 under control of the CPU 101.Similarly, in the case where an external microphone is connected or anexternal speaker is connected, the external microphone or the externalspeaker is driven in preference to the built-in microphone 114 or thebuilt-in speaker 115 under control of the CPU 101.

The recording medium 106 is removable from the communication terminal10. In addition, a non-volatile memory that reads or writes data undercontrol of the CPU 101 is not limited to the flash memory 104, and anelectrically erasable and programmable read-only memory (EEPROM) may beused instead.

<Hardware Configuration of Communication Management System and RelayDevice>

Referring to FIG. 3, a hardware configuration of the communicationmanagement system 50 and the relay device 30 is described according toan embodiment of the present invention. The communication managementsystem 50, which may be implemented by a server computer, includes acentral processing unit (CPU) 501, a read only memory (ROM) 502, arandom access memory (RAM) 503, a hard disk (HD) 504, a hard disk drive(HDD) 505, a recording medium 506, a medium I/F 507, a display 508, anetwork I/F 509, a keyboard 511, a mouse 512, a CD-ROM drive 514, and abus line 510.

The CPU 510 controls entire operation of the communication managementsystem 50. The ROM 502 stores a control program for controlling the CPU501 such as an IPL. The RAM 503 is used as a work area for the CPU 501.The HD 504 stores various data such as the communication managementprogram. The HDD 505 controls reading or writing of various data to orfrom the HDD 504 under control of the CPU 501. The medium I/F 507controls reading or writing of data with respect to a recording medium506 such as a flash memory. The display 508 displays various informationsuch as a cursor, menu, window, characters, or image. The network I/F509 allows communication of data with an external device through thecommunication network 2 such as the Internet. The keyboard 511 is oneexample of input device provided with a plurality of keys for allowing auser to input characters, numerals, or various instructions. The mouse512 is one example of input device for allowing the user to select aspecific instruction or execution, select a target for processing, ormove a curser being displayed. The CD-ROM drive 514 reads or writesvarious data with respect to a CD-ROM 513, which is one example ofremovable recording medium.

The bus line 510 may be an address bus or a data bus, which electricallyconnects various elements such as the CPU 501 of FIG. 3.

Since the relay device 30 in FIG. 1 is substantially similar in hardwareconfiguration to the communication management system 50, the descriptionthereof is omitted. The relay device 30, however, stores a relay controlprogram in the HD 504 in alternative to the management program.

<Hardware Configuration of Electronic Whiteboard>

FIG. 4 illustrates a hardware configuration of the communicationterminal 70, when implemented by the electronic whiteboard, according tothe embodiment. As illustrated in FIG. 4, the electronic whiteboard 70,as an example of communication terminal 70, includes a CPU 701, a ROM702, a RAM 703, a SSD 704, a network controller 705, and an externaldevice connection I/F 706, which are connected through a bus line 710.

The CPU 701 controls entire operation of the electronic whiteboard 70.The ROM 702 stores a control program for controlling the CPU 701 such asan IPL. The RAM 503 is used as a work area for the CPU 701. The SSD 704stores various data such as the control program for the electronicwhiteboard 70. The network controller 705 controls communication with anexternal device through the communication network 2. The external deviceconnection I/F 706 controls communication with an external device suchas a USB memory 755, and external devices such as a camera 762, aspeaker 765, a microphone 764, etc.

The electronic whiteboard 70 further includes a capturing device 711, agraphics processing unit (GPU) 712, a display controller 713, a sensorcontroller 714, a contact sensor 715, an electronic pen controller 716,a near-distance communication circuit 719, and an antenna 719 a for thenear-distance communication circuit 719.

The capturing device 711 causes a display of a notebook PC 756 todisplay a video image or a still image based on image data that iscaptured by the capturing device 711. In this way, the image beingdisplayed on a display 753 of the electronic whiteboard 70 can be sharedwith the external display. The GPU 712 is a semiconductor chip dedicatedto processing a graphical image. The display controller 713 controlsdisplay of an image processed at the GPU 712 for output through thedisplay 753 provided with the electronic whiteboard 70. The contactsensor 715 detects a touch onto the display 753 with an electronic pen754 or a user's hand H. The sensor controller 714 controls operation ofthe contact sensor 715. The contact sensor 715 senses a touch input to aspecific coordinate on the display 735 using the infrared blockingsystem. More specifically, the display 753 is provided with two lightreceiving elements disposed on both upper side ends of the display 753,and a reflector frame. The light receiving elements emit a plurality ofinfrared rays in parallel to a touch panel of the display 753. The lightreceiving elements receive lights passing in the direction that is thesame as an optical path of the emitted infrared rays, which arereflected by the reflector frame. The contact sensor 715 outputs anidentifier (ID) of the infrared ray that is blocked by an object (suchas the user's hand) after being emitted from the light receivingelements, to the sensor controller 714. Based on the ID of the infraredray, the sensor controller 715 detects a specific coordinate that istouched. The electronic pen controller 716 communicates with theelectronic pen 754 to detect a touch by the tip or bottom of the pen 754to the display 753. The near-distance communication circuit 719 is acommunication circuit that communicates in compliance with the NFC(Registered Trademark), the Bluetooth (Registered Trademark), and thelike.

The bus line 710 is an address bus or a data bus, which electricallyconnects the elements in FIG. 4 such as the CPU 701.

The contact sensor 715 is not limited to the infrared blocking systemtype, and may be a different type of detector, such as a capacitancetouch panel that identifies the contact position by detecting a changein capacitance, a resistance film touch panel that identifies thecontact position by detecting a change in voltage of two opposedresistance films, or an electromagnetic induction touch panel thatidentifies the contact position by detecting electromagnetic inductioncaused by contact of an object to a display. In addition or inalternative to detecting a touch by the tip or bottom of the pen 754,the electronic pen controller 716 may also detect a touch by anotherpart of the electronic pen 754, such as a part held by a hand.

<Hardware Configuration of Mobile Terminal>

FIG. 5 illustrates a hardware configuration of a mobile terminal,according to the embodiment of the present invention. As illustrated inFIG. 5, the communication terminal 90, which may be implemented by amobile terminal such as a smart phone, includes a CPU 901, a ROM 902, aRAM 903, an Electrically Erasable and Programmable ROM (EEPROM) 904, aComplementary Metal Oxide Semiconductor (CMOS) sensor 905, anacceleration and orientation sensor 906, a medium I/F 908, and a GPSreceiver 909, which are connected through a bus line 910.

The CPU 901 controls entire operation of the smart phone 90. The ROM 902stores a control program for controlling the CPU 901 such as an IPL. TheRAM 903 is used as a work area for the CPU 901. The EEPROM 904 reads orwrites various data such as a communication terminal control programunder control of the CPU 901. The CMOS sensor 905 captures an objectunder control of the CPU 901 to obtain captured image data. Theacceleration and orientation sensor 906 includes various sensors such asan electromagnetic compass or gyrocompass for detecting geomagnetism,and an acceleration sensor. The medium I/F 908 controls reading orwriting of data with respect to a recording medium 907 such as a flashmemory. The GPS receiver 909 receives a GPS signal from a GPS satellite.

The communication terminal 90 further includes a far-distancecommunication circuit 911, a camera 912, an imaging element I/F 913, amicrophone 914, a speaker 915, an audio input/output I/F 916, a display917, an external device connection I/F 918, a near-distancecommunication circuit 919, an antenna 919 a for the near-distancecommunication circuit 919, and a touch panel 921.

The far-distance communication circuit 911 is a circuit thatcommunicates with the other device through a communication network 3such as a mobile communication network. The camera 912 is an example ofimaging device capable of capturing a subject under control of the CPU901, and is incorporated in the communication terminal 90, which is thesmart phone. The imaging element device I/F 913 is a circuit thatcontrols driving of the camera 912. The microphone 914 is an example ofaudio collecting device capable of inputting audio under control of theCPU 901, and is incorporated in the communication terminal 90. The audioI/O I/F 916 is a circuit for inputting or outputting an audio signalbetween the microphone 914 and the speaker 915 under control of the CPU901. The display 915 may be a liquid crystal or organicelectro-luminescence (EL) display that displays an image of a subject,an operation icon, or the like. The external device connection I/F 918is an interface circuit that connects the terminal 90 to variousexternal devices. The near-distance communication circuit 919 is acommunication circuit that communicates in compliance with the NFC(Registered Trademark), the Bluetooth (Registered Trademark), and thelike. The touch panel 921 is an example of input device that enables theuser to input a user instruction through touching a screen of thedisplay 917.

The bus line 910 is an address bus or a data bus, which electricallyconnects the elements in FIG. 5 such as the CPU 901.

The communication terminal 90 may be implemented by a tablet, a smartwatch, portable phone, or portable game machine.

Further, the terminal control program may be recorded in a file in aformat installable or executable on a computer-readable recording mediumsuch as the recording medium 907 for distribution. Examples of therecording medium include, but not limited to, a compact disc-recordable(CD-R), digital versatile disc (DVD), blue-ray disc, and SD card.

<Software Configuration of Communication Terminal>

FIG. 6A illustrates a software configuration of the communicationterminal 10 as the videoconference terminal according to the embodimentof the invention. As illustrated in FIG. 6A, the communication terminal10 is installed with an operating system (OS) 1020, activationapplication 1030, first communication application A1, secondcommunication application A2, and third communication application A3,each of which operates on a work area 1010 of the RAM 103. The OS 1020is basic software that controls entire operation of the videoconferenceterminal 10 through providing basic functions. The activationapplication 1030 activates the system, for example, when the terminal isturned on.

The communication application A1, A2, and A3 each enable thevideoconference terminal 10 to communicate with the other communicationterminal, using different communication protocols. The communicationprotocol is defined by, for example, a call control protocol and animage encoding format. Examples of the call control protocol being usedby the terminal 10 include, but not limited to, (1) session initialprotocol (SIP), (2) H.323, (3) the extended SIP, (4) Instant Messenger(IM) Protocol such as extensible messaging and presence protocol (XMPP),ICQ (Registered Trademark), AIM (Registered Trademark), or Skype(Registered Trademark), (5) protocol using the SIP message method, (6)Internet relay chat (IRC) protocol, and (7) extended IM based protocolsuch as Jingle. Examples of the image encoding format include, but notlimited to, H. 264/SVC, H.264/AVC, and H.265/HEVC.

FIG. 6B illustrates a software configuration of the communicationterminal 70 as the electronic whiteboard according to the embodiment ofthe invention. As illustrated in FIG. 6B, the communication terminal 70is installed with an OS 7020, activation application 7030, firstcommunication application A1, second communication application A2, andthird communication application A3, each of which operates on a workarea 7010 of the RAM 703.

The OS 7020 is basic software that controls entire operation of theelectronic whiteboard 70 through providing basic functions. Theactivation application 7030 activates the system, for example, when theterminal is turned on. The communication application A1, A2, and A3 arethe same as the communication A1, A2, and A3 installed with thevideoconference terminal 10, respectively. While this exampleillustrates only three types of communication application beinginstalled, any number (one, two, or more than four) of types ofcommunication application may be installed on any one of thecommunication terminals.

It is assumed that the OS (1020 or 7020), and the communicationapplication A1, A2, and A3 are installed onto the communication terminal(10 or 70) before shipment to a user side.

Alternatively, application may be added or deleted after shipment, forexample, when software (control program) of the communication terminalis updated. More specifically, after being shipped to the user, thecommunication terminal may access the communication management system 50or any other server to download the upgraded version, or new, software.Further, the communication terminal may replace the existing softwarewith the new version, or upgraded version, of software (control program)being downloaded. In case of updating the control program, applicationbeing installed on the communication terminal such as the communicationapplication A1 to A3 may be upgraded.

<Configuration of Communication System>

Referring now to FIG. 7, a configuration of the communication system 1is described according to the embodiment. FIG. 7 is a schematic diagramillustrating a network configuration of the communication system 1 ofFIG. 1.

In FIG. 7, the communication terminals such as the videoconferenceterminal 10 and the electronic whiteboard 70, the relay device 30, andthe communication management system 50, are connected to thecommunication network 2 including the Internet. The communicationnetwork 2 may include wireless network, in addition to wired network. Inthis example, the communication terminal 10 is provided at a site A, andthe communication terminal 70 is provided at a site D. For example, thesite A may be Japan, and the site B may be England. At the site A, auser X has a mobile terminal 90 a, which is one example of mobileterminal. The user X also operates the communication terminal 10. At thesite D, the user Y operates the communication terminal 70. In thisexample illustrated in FIG. 7, the user X usually works at the site D(England), but temporarily visits the site A (Japan). In such case,before leaving for the site A, the user X stores information to be usedfor accessing the communication terminal 70 at the site D, in the mobileterminal 90 a. At the site A, the user X operates the communicationterminal 10 to communicate with the communication terminal 70, using theinformation stored in the mobile terminal 90 a.

<Functional Configuration of Embodiment

Referring now to FIGS. 2 to 5 and 8, a functional configuration of thecommunication system 1 of FIG. 1 is described according to theembodiment of the present invention. FIG. 8 is a schematic block diagramillustrating a functional configuration of the communication system 1 ofFIG. 1 according to the embodiment of the present invention.

<Functional Configuration of Terminal>

The terminal 10 includes a transmitter/receiver 11, an acceptor 12, acommunication control 13, a display control 14, a determiner 15, aselector 16, an activator 17, an obtainer/provider 18, and a memorycontrol 19. These units are functions that are implemented by or thatare caused to function by operating any of the hardware componentsillustrated in FIG. 2 in cooperation with the instructions of the CPU101 according to the communication control program expanded from theflash memory 104 to the RAM 103. The communication terminal 10 furtherincludes a memory 1000 configured by the RAM 103 illustrated in FIG. 2,and the flash memory 104 illustrated in FIG. 2. The communicationterminal 10 may be provided with a recording medium 1100 that isremovable.

(Functional Configuration of Communication Terminal)

Next, a functional configuration of the communication terminal 10 isdescribed in detail. The transmitter/receiver 11, which may beimplemented by the instructions of the CPU 101, the network I/F 111, andthe external device connection I/F 118, illustrated in FIG. 2, transmitsor receives various data (or information) to or from the other terminal,apparatus, or system through the communication network 2. Beforestarting communication with a counterpart terminal, thetransmitter/receiver 11 starts receiving terminal state informationindicating an operating state of each communication terminal as acandidate counterpart terminal, from the communication management system50. The state information not only indicates the operating state of eachcommunication terminal (whether the communication terminal is online oroffline), but also indicates a detailed state such as whether thecommunication terminal whose state is online is now capable ofcommunicating or is currently communicating, or the user of thecommunication terminal is not at the communication terminal.Hereinafter, the case in which the state information indicates theoperating state will be described by way of example.

The transmitter/receiver 11 further controls processing to startcommunication between the communication terminal 10 and a counterpartcommunication terminal such as the communication terminal 70.

The acceptor 12, which is implemented by the instructions of the CPU 101illustrated in FIG. 2 and by the operation key 108 and the power switch109 illustrated in FIG. 2, accepts various inputs from the user.

The communication control 13 is implemented by the instructions of theCPU 101, and any desired device relating to input or output of contentdata. In one example, the communication control 13 is implemented by theinstructions of the CPU 101 illustrated in FIG. 2 and by the camera 112and the imaging element I/F 113 illustrated in FIG. 2. The communicationcontrol 13 captures an image of a subject and outputs image dataobtained by capturing the image. In one example, the communicationcontrol 13 is implemented by the instructions of the CPU 101 illustratedin FIG. 2 and by the audio input/output I/F 116 illustrated in FIG. 2.After the sound of the user is converted to an audio signal by themicrophone 114, the communication control 13 receives audio dataaccording to this audio signal. In another example, the communicationcontrol 13 is implemented by the instructions of the CPU 101 illustratedin FIG. 2 and by the audio input/output I/F 116 illustrated in FIG. 2,and outputs the audio signal according to the audio data to the speaker115, and the speaker 115 outputs audio.

The display control 14 is implemented by the instructions of the CPU 101illustrated in FIG. 2 and by the display I/F 117 illustrated in FIG. 2.The display control 14 combines images of different resolutions andtransmits the combined image to the display 120. The display control 14also transmits information on a contact list, received from themanagement system 50, to the display 120, and controls display of thecontact list on the display 120.

The determiner 15, which may be implemented by the instructions of theCPU 101 illustrated in FIG. 2, determines whether any communicationterminal, such as the mobile terminal, is located within a predetermineddistance from the communication terminal 10. The selector 16, which maybe implemented by the instructions of the CPU 101 according to theactivation application 1030 of FIG. 6A, selects communicationapplication to be activated based on the terminal identificationinformation of the counterpart communication terminal.

For example, in case the terminal identification information is aterminal ID, the first communication application A1 is selected. Theselector 16 analyzes a description format of the terminal identificationinformation to determine whether it is a sequence of characters and/ormarks.

In case the terminal identification information is a terminal IPaddress, the second communication application A2 is selected. In thisexample, the terminal IP address may be an IP address, which is used foraccessing the counterpart communication terminal. If a descriptionformat of the terminal identification information indicates 32-bitnumerals with four sets of 8-bit numerals (in case of IPv4), theselector 16 determines that the terminal identification information isthe terminal IP address.

In case the terminal identification information is an email address, thethird communication application A3 is selected. In this example, theemail address is used to identify a communication destination of thecommunication terminal. The email address is expressed as a string ofcharacters as defined by RFC2822. The selector 16 specificallydetermines whether a left of the mark “@” is a domain name, and a rightof the mark “@” is an email server.

In the above-described embodiment, the communication application A1 isselected in case the terminal identification information is a terminalID, the communication application A2 is selected in case the terminalidentification information is an IP address, and the communicationapplication A3 is selected in case the terminal identificationinformation is an email address. Such combination of a type of theterminal identification information and a type of communicationapplication is determined by a description format of the terminalidentification information applicable to the communication application.For this reason, any other combination may be used. For example, otherexamples of the terminal identification information include a user IDidentifying the user operating the counterpart communication terminal,and a user name of the user operating the counterpart communicationterminal. In such case, communication application applicable to adescription format of the terminal identification information for suchuser ID or user name is selected. In case none of communicationapplication being installed with the communication terminal (startingterminal) is applicable to the terminal identification information ofthe counterpart communication terminal, the communication terminal maycontrol its display to display a message indicating that nocommunication application applicable to the terminal identificationinformation of the counterpart communication terminal is available, or amessage requesting a user to install communication applicationapplicable to the terminal identification information of the counterpartcommunication terminal.

The activator 17, which may be implemented by the instructions of theCPU 101 according to the activation application 1030 of FIG. 6A,activates the communication application selected by the selector 16.

The obtainer/provider 18, which may be implemented by the instructionsof the CPU 101, and the near-distance communication circuit 119 with theantenna 119 a, illustrated in FIG. 2, communicates with the counterpartcommunication terminal such as the mobile terminal 90 to transmit(provide) data or receive (obtain) data to or from the counterpartcommunication terminal.

The memory control 19, which is implemented by the instructions of theCPU 101 and the SSD 105 illustrated in FIG. 2, or by the instructions ofthe CPU 101, performs processing to store various types of data in thememory 1000 or the recording medium 1100 or to read various types ofdata stored in the memory 1000 or the recording medium 1100. Further,every time image data and audio data are received in performingcommunication with a counterpart terminal, the memory 1000 overwritesthe image data and audio data. The display 120 displays an image basedon image data before being overwritten, and the speaker 115 outputsaudio based on audio data before being overwritten. The recording medium1100 is implemented by the recording medium 106 illustrated in FIG. 2.

Note that the terminal identification information in the embodiment isan example of identification information that is used to uniquelyidentify a specific communication terminal (10, 70) or the useroperating such terminal, such that a language, a character(s), asymbol(s), or various marks are not limited to the above-describedembodiment. For example, a combination of at least two of theabove-mentioned language, character(s), symbol(s), and various marks maybe used as the terminal identification information. Further, the user IDmay include a name of the user, the individual number that uniquelyassigns each user such as a social security number, etc.

<Functional Configuration of Relay Device>

The relay device 30 includes a transmitter/receiver 31, a determiner 32,and a memory control 39. These units are functions that are implementedby or that are caused to function by operating any of the elementsillustrated in FIG. 3 in cooperation with the instructions of the CPU501 according to the relay device control program expanded from the HD504 to the RAM 503. The relay device 30 also includes a memory 3000implemented by the RAM 504 illustrated in FIG. 3 and/or the HD 504illustrated in FIG. 3.

(Functional Configuration of Relay Device)

Next, a functional configuration of the relay device 30 is described indetail. In the following description of functional configuration of therelay device 30, relationships of the hardware elements in FIG. 3 withthe functional configuration of the relay device 30 in FIG. 8 will alsobe described.

The transmitter/receiver 31 of the relay device 30 illustrated in FIG.8, which is implemented by the instructions of the CPU 501 illustratedin FIG. 3 and by the network I/F 509 illustrated in FIG. 3, transmits orreceives various types of data (or information) to or from anotherterminal, device, or system via the communication network 2. Thetransmitter/receiver 31 also serves as a transferer, which transferscontent data transmitted from one communication terminal (such as thecommunication terminal 10) to another communication terminal (such asthe communication terminal 70).

The determiner 32, which may be implemented by the instructions of theCPU 501 illustrated in FIG. 3, determines delay of data transmission.

The memory control 39, which may be implemented by the instructions ofthe CPU 501 illustrated in FIG. 3 and the HDD 505 illustrated in FIG. 3,performs processing to store various types of data in the memory 3000 orread various types of data stored in the memory 3000.

<Functional Configuration of Management System>

The communication management system 50 includes a transmitter/receiver51, a determiner 52, and a memory control 59. These units are functionsthat are implemented by or that are caused to function by operating anyof the elements illustrated in FIG. 8 in cooperation with theinstructions of the CPU 501 according to the communication managementprogram expanded from the HD 504 to the RAM 503. In addition, thecommunication management system 50 includes a memory 5000 implemented bythe HD 504 illustrated in FIG. 3.

(Authentication Management Table)

FIG. 9 is an illustration of an example data structure of anauthentication management table. The memory 5000 stores anauthentication management DB 5001 such as the authentication managementtable illustrated in FIG. 9. The authentication management table stores,for each one of the terminals (10, 70) managed by the communicationmanagement system 50, the terminal ID and the password in associationwith each other. For example, the authentication management tableillustrated in FIG. 9 indicates that the terminal ID of the terminal 10aa is “01aa”, and the password of the terminal 10 aa is “aaaa”.

(Terminal Management Table)

FIG. 10 is an illustration of an example data structure of a terminalmanagement table. The memory 5000 stores a terminal management DB 5002such as the terminal management table illustrated in FIG. 10. Theterminal management table stores, for each one of the terminals (such asthe communication terminals 10 and 70) managed by the communicationmanagement system 50, the terminal ID of the terminal, a counterpartterminal name in the case where the terminal serves as a counterpartterminal, the operating state of the terminal, a date/time received atwhich login request information described later is received at thecommunication management system 50, and the IP address of the terminal,in association with one another. For example, the terminal managementtable illustrated in FIG. 10 indicates that the terminal 10 aa with theterminal ID “01aa” has the counterpart terminal name “AA terminal, Tokyooffice, Japan”, the operating state “online (communication OK)”, thedate/time received at which login request information is received by themanagement system 50 “Apr. 10, 2015, 13:40”, and the IP address“1.2.1.3”. The terminal ID, the terminal (counterpart) name, and theterminal IP address in the terminal management table of FIG. 10 isregistered by the communication management system 50, when thecommunication management system 50 accepts registration of eachcommunication terminal (10, 70) that requests services from thecommunication management system 50.

(Contact List Management Table)

FIG. 11 is an illustration of an example data structure of a contactlist management table. The memory 5000 further stores a contact listmanagement DB 5003 implemented by the contact list management tableillustrated in FIG. 11. The contact list management table stores, foreach one of the terminals managed by the communication management system50, the terminal ID of the terminal (starting terminal) that requests tostart communication, in association with the terminal IDs of allcounterpart terminals registered as candidate counterpart terminals forthe starting terminal. For example, the contact list management tableillustrated in FIG. 11 indicates that candidates for a counterpartterminal to which a starting terminal (terminal 10 aa) whose terminal IDis “01aa” can send a request to start communication in a videoconferenceare the terminal 10 ab whose terminal ID is “01ab”, the terminal 10 bawhose terminal ID is “01ba”, the terminal 70 bb whose terminal ID is“07bb”, and so forth. Note that the terminal 70 bb is one example of thecommunication terminal 70, as the electronic whiteboard 70 in FIG. 7.The candidate counterpart terminals are updated by addition or deletionin response to an addition or deletion request received from anarbitrary terminal (starting terminal) to the management system 50.

The contact list is just one example of contact information indicating acandidate of counterpart communication terminals, such that the contactinformation may be managed in various ways other than in the form ofcontact list, as long as the counterpart terminal information isassociated with the starting terminal.

(Addition Request Management Table)

FIG. 12 is an illustration of an example data structure of an additionrequest management table. The memory 5000 stores an addition requestmanagement DB 5004 such as the addition request management tableillustrated in FIG. 12. The addition request management table storesinformation regarding an addition request that requests to add aterminal as a candidate counterpart terminal for a terminal. Theaddition request management table stores, for each addition request, aterminal ID of the communication terminal that sends the additionrequest (“request sender terminal”), and a terminal ID of thecommunication terminal that is requested to be added (“requestdestination terminal”), in association with each other.

(Functional Configuration of Management System)

Next, referring back to FIG. 7, a functional configuration of thecommunication management system 50 will be described in detail. In thefollowing description of a functional configuration of the communicationmanagement system 50, relationships of the hardware configuration ofFIG. 3 with a functional configuration of the management system 50 inFIG. 7 will also be described.

The transmitter/receiver 51, which is implemented by the instructions ofthe CPU 501 illustrated in FIG. 3 and by the network I/F 509 illustratedin FIG. 3, transmits or receives various types of data (or information)to or from another terminal, device, or system via the communicationnetwork 2.

The determiner 15, which may be implemented by the instructions of theCPU 501 illustrated in FIG. 3, outputs a determination result.

The memory control 59, which may be implemented by the instructions ofthe CPU 501 illustrated in FIG. 3 and the HDD 505 illustrated in FIG. 3,performs processing to store various types of data in the memory 5000 orread various types of data stored in the memory 5000.

<Functional Configuration of Communication Terminal>

The communication terminal 70 includes a transmitter/receiver 71, anacceptor 72, a communication control 73, a display control 74, adeterminer 75, a selector 76, an activator 77, an obtainer/provider 78,and a memory control 79. These units are functions that are implementedby or that are caused to function by operating any of the elementsillustrated in FIG. 4 in cooperation with the instructions of the CPU701 according to the communication control program expanded from the SSD704 to the RAM 703. The communication terminal 70 further includes amemory 7000 configured by the RAM 703 illustrated in FIG. 4, and the SSD704 illustrated in FIG. 4. The communication terminal 70 may be providedwith a recording medium 7100 that is removable.

(Functional Configuration of Communication Terminal)

Next, a functional configuration of the communication terminal 70 isdescribed in detail. The transmitter/receiver 71, which may beimplemented by the instructions of the CPU 701, the network controller705, and the external device connection I/F 706, illustrated in FIG. 4,transmits or receives various data (or information) to or from the otherterminal, apparatus, or system through the communication network 2.Before starting communication with a counterpart terminal, thetransmitter/receiver 71 starts receiving terminal state informationindicating an operating state of each communication terminal as acandidate counterpart terminal, from the communication management system50. The state information not only indicates the operating state of eachcommunication terminal (whether the communication terminal is online oroffline), but also indicates a detailed state such as whether thecommunication terminal whose state is online is now capable ofcommunicating or is currently communicating, or the user of thecommunication terminal is not at the communication terminal. Inaddition, the state information not only indicates the operating stateof each terminal, but also indicates various states, such as the statethat the cable 120 c is disconnected from the terminal, the state thatthe terminal can output sounds but not images, or the state that theterminal is muted. Hereinafter, the case in which the state informationindicates the operating state will be described by way of example.

The transmitter/receiver 71 further controls processing to startcommunication with the other communication terminal such as thecounterpart communication terminal 10. The acceptor 72, which isimplemented by the instructions of the CPU 701, the contact sensor 715,and the electronic pen controller 716, illustrated in FIG. 4, acceptsvarious inputs from the user.

The communication control 73 is implemented by the instructions of theCPU 701, in cooperation with any desired device relating to input oroutput of content data. In one example, the communication control 13applies image processing to an image captured by the camera 762. Inanother example, the communication control 73, after the audio of theuser is converted to an audio signal by the microphone 764, thecommunication control 13 processes audio data based on this audiosignal. In another example, the communication control 73 outputs theaudio signal according to the audio data to the speaker 765, and thespeaker 765 outputs audio.

In another example, the communication control 73 obtains drawing data,drawn by the user with the electronic pen 754 or the user's hand H ontothe display 753, and converts the drawing data to coordinate data.Further, when the communication terminal 70 transmits the coordinatedata to the other communication terminal 70, the other communicationterminal causes the display 753 to display drawing data based on thecoordinate data received from the communication terminal 70.

The display control 74 is implemented by the instructions of the CPU 701illustrated in FIG. 4 and by the display controller 713 illustrated inFIG. 4. The display control 74 combines images of different resolutionsand transmits the combined image to the display 753. The display control74 also transmits information on a contact list, received from thecommunication management system 50, to the display 753, and controlsdisplay of the contact list on the display 753.

The determiner 75, which may be implemented by the instructions of theCPU 701 illustrated in FIG. 4, determines whether any communicationterminal, such as the mobile terminal 90, is within a predetermineddistance from the communication terminal 70.

The activator 77, which may be implemented by the instructions of theCPU 701 according to the activation application 7030 of FIG. 6B,activates the communication application selected by the selector 76. Theselector 76 selects the communication application to be activated, fromthe communication application A1, A2, and A3 of FIG. 6B, in asubstantially similar manner as described above for the case of theselector 16 of the communication terminal 10.

The obtainer/provider 78, which may be implemented by the instructionsof the CPU 701, the near-distance communication circuit 719 with theantenna 719 a, illustrated in FIG. 4, communicates with the counterpartcommunication terminal to transmit (provide) data or receive (obtain)data to or from the counterpart communication terminal.

The memory control 79, which is implemented by the instructions of theCPU 701 and the SSD 704 illustrated in FIG. 4, or by the instructions ofthe CPU 701, performs processing to store various types of data in thememory 7000 or the recording medium 7100 or to read various types ofdata stored in the memory 7000 or the recording medium 7100. Further,every time image data and audio data are received in performingcommunication with a counterpart terminal, the memory 7000 overwritesthe image data and audio data. The display 753 displays an image basedon image data before being overwritten, and the speaker 765 outputsaudio based on audio data before being overwritten. The recording medium7100 is implemented by the USB memory 755 illustrated in FIG. 4.

<Functional Configuration of Communication Terminal>

The functional configuration of the communication terminal 90 a isdescribed as an example.

The mobile terminal 90 a includes a transmitter/receiver 91 a, anacceptor 92 a, a communication control 93 a, a display control 94 a, adeterminer 95 a, an obtainer/provider 98 a, and a memory control 99 a.These units are functions that are implemented by or that are caused tofunction by operating any of the hardware elements illustrated in FIG. 5in cooperation with the instructions of the CPU 901 according to thecommunication control program expanded from the EEPROM 904 to the RAM903. The communication terminal 90 a further includes a memory 9000 aconfigured by the RAM 903 illustrated in FIG. 5, and the EEPROM 704illustrated in FIG. 5. The communication terminal 90 a may be providedwith a recording medium 9100 a that is removable.

(Functional Configuration of Mobile Terminal)

Next, a functional configuration of the mobile terminal 90 a isdescribed in detail. The transmitter/receiver 91 a, which may beimplemented by the instructions of the CPU 901, and the near-distancecommunication circuit 911 with the antenna 911 a, illustrated in FIG. 5,transmits or receives various data (or information) to or from the otherterminal, apparatus, or system through the communication network 3.

The acceptor 92 a, which is implemented by the instructions of the CPU901 illustrated in FIG. 5 and by the touch panel 921 illustrated in FIG.5, accepts various inputs from the user.

The communication control 93 a is implemented by the instructions of theCPU 901 in cooperation with any desired device relating to input oroutput of content data. In one example, the communication control 93 a,implemented by the instructions of the CPU 901 in cooperation with theimaging element I/F 913, applies image processing to an image capturedby the camera 912. In another example, the communication control 93 a isimplemented by the instructions of the CPU 901 in cooperation with theaudio input/output I/F 916. After the audio of the user is converted toan audio signal by the microphone 914, the communication control 93 aprocesses audio data based on this audio signal. In another example, thecommunication control 93 a, implemented by the instructions of the CPU901 and the audio input/output I/F 916, outputs the audio signalaccording to the audio data to the speaker 915, and the speaker 915outputs audio.

The display control 94 a, which may be implemented by the instructionsof the CPU 901, controls display of an image based on the image datathrough the display 917.

The determiner 95 a, which may be implemented by the instructions of theCPU 901 illustrated in FIG. 5, outputs a determination result.

The obtainer/provider 98 a, which may be implemented by the instructionsof the CPU 901, and the near-distance communication circuit 919 with theantenna 919 a, illustrated in FIG. 5, communicates with the counterpartcommunication terminal to transmit (provide) data or receive (obtain)data to or from the counterpart communication terminal.

The memory control 99 a, which may be implemented by the instructions ofthe CPU 901 and the EEPROM 904, illustrated in FIG. 5, performsprocessing to store various types of data in the memory 9000 a or 9100 aor read various types of data stored in the memory 9000 a or 9100 a.

(Data Structure of Near-Distance Communication Circuit)

FIG. 13 illustrates a data structure of a near-distance communicationcircuit. The near-distance communication circuit 919 has a datastructure as illustrated in FIG. 13. With this data structure, thenear-distance communication circuit 919 manages data by block number.For instance, a storage area with the block No. 1 stores an identifierof the near-distance communication circuit 919, and a storage area withthe block No. 2 stores a user name of the mobile terminal 90 having thenear-distance communication circuit 919.

The storage areas with the block Nos. 3 to 5 are each for storing theterminal identification information of the communication terminal 10 or70, which is obtained by the mobile terminal 90 by near-distancecommunication. The storage areas with the block Nos. 3, 4, and 5respectively correspond to the terminal ID, the IP address, and theemail address. For example, if the terminal ID “07db” is obtained at themobile terminal 90 a as the terminal identification information of thecommunication terminal 70, the near-distance communication circuit 919of the mobile terminal 90 a stores the terminal ID “07db” in the storagearea with the block No. 3.

The storage areas with the block Nos. 6 to 8 are each for storing theterminal identification information of the communication terminal 10 or70, which is received at the local mobile terminal 90 from thecounterpart mobile terminal 90 via the communication network 3. Thestorage areas with the block Nos. 6, 7, and 8 respectively correspond tothe terminal ID, the IP address, and the email address.

<Operation>

Referring to FIGS. 14 to 22, operation performed by the communicationsystem 1 is explained according to an embodiment of the presentinvention. In this following example, it is assumed that the user X(Kato) at the site A requests to have a videoconference with the user Y(James) at the site D. More specifically, the user X at the site Dobtains the terminal ID of the communication terminal 70, for example,by bringing the mobile terminal 90 a close to the communication terminal70. After moving to the site A, the user X brings the mobile terminal 90a, which stores the terminal ID of the communication terminal 70, closeto the communication terminal 10 to send the terminal ID of thecommunication terminal 70 to the communication terminal 10. Thecommunication terminal 10, which receives the terminal ID of thecommunication terminal 70, can then start videoconference with thecommunication terminal 70 via the communication network 2. Beforecalling with the communication terminal 10, the user X at the site A maycall a mobile terminal of the user Y.

The communication terminal 70 db is one example of the communicationterminal 70, which is located at the site D to be operated by the user Yto start videoconference. FIG. 14 is a data sequence diagramillustrating operation of providing the terminal identificationinformation. FIG. 15 is a screen to be displayed in providing theterminal identification information. In this example, the terminal ID isused as the terminal identification information of the communicationterminal 70 db.

As the user X at the site D operates the communication terminal 70 dbwith the electronic pen 754 or the user's hand H, the acceptor 72 of thecommunication terminal 70 db accepts an instruction for displaying aterminal identification information providing screen (S21). The displaycontrol 74 causes the display 753 to display the providing screen asillustrated in FIG. 15 (S22).

The determiner 75 determines whether the mobile terminal 90 a is broughtsufficiently close to the communication terminal 70 db (S23). Thefollowing assumes the case in which the user X brings the mobileterminal 90 a close to the communication terminal 70 db.

The memory control 79 of the communication terminal 70 db reads out theterminal ID of the communication terminal 70 db from the memory 7000(S24).

The obtainer/provider 78 transmits a request for recording the terminalID (“recording request”) to the mobile terminal 90 a by near-distancewireless communication (S25). The recording request includes theterminal ID that is read at S24, and recording area indicating an areawhere such terminal ID is to be recorded. The obtainer/provider 98 ofthe mobile terminal 90 a receives the recording request. Theobtainer/provider 98 obtains the terminal ID and the recording areainformation. The memory control 99 a stores the terminal ID in thememory 9000 a, as indicated by the recording area information (S27). Forexample, as illustrated in FIG. 13, the terminal ID of the communicationterminal 70 db is stored in an area identified with the block No. 3. Inthe meantime, after transmitting the recording request at S25, thedisplay control 74 of the communication terminal 70 db closes theproviding screen (S26).

Referring to FIGS. 16 and 17, operation of preparing for communicationbetween the communication terminal 10 aa and the communication terminal10 ab is explained according to an embodiment of the present invention.FIG. 16 is a data sequence diagram illustrating operation of preparingfor communication between the terminal 10 aa and the terminal 10 ab.FIG. 17 is an example screen of a contact list for display at theterminal 10 aa.

In this example, the communication terminal 10 aa corresponds to thecommunication terminal 10 of FIG. 7. The communication terminal 10 ab isalso a videoconference terminal, which can be a counterpart terminal forthe communication terminal 10 aa. For simplicity, in FIG. 16, only thecommunication terminal 10 aa and the communication terminal 10 ab, whichare communicable via the communication management system 50, areillustrated.

First, when the user X presses the operation key 108 illustrated in FIG.2 to request for activation of the activation application 1030, theacceptor 12 of the terminal 10 aa accepts a request for activating theactivation application 1030, and activates the activation application1030 (S61). The transmitter/receiver 11 of the terminal 10 aa transmitslogin request information indicating a login request to thecommunication management system 50 via the communication network 2(S62). The login request information includes a terminal ID foridentifying the terminal 10 aa, which is a local terminal serving as astarting terminal, and a password. The terminal ID and the password aredata that have been read via the memory control 19 from the memory 1000and sent to the transmitter/receiver 11.

Next, the memory control 59 of the management system 50 performsterminal authentication by searching the authentication management tableof FIG. 9 using the terminal ID and the password included in the loginrequest information received via the data transmitter/receiver 51 assearch keys, and determining whether the same terminal ID and the samepassword are managed in the authentication management table of FIG. 9(S63). In the case where the memory control 59 determines that the loginrequest is a login request received from the authenticated terminalsince the same terminal ID and the same password are managed, the memorycontrol 59 stores, in a record for the terminal ID received at S62 inthe terminal management table of FIG. 10, the operating state (Online(communication OK), and the date/time received at which theabove-described login request information is received. For example, ifthe terminal 10 aa has the terminal ID “01aa”, the memory control 59stores the operating state “Online (Communication OK)” and the date/timereceived “4.10.2015.13:40” in association with the terminal ID “01aa” inthe terminal management table illustrated in FIG. 10. Further, in thisexample, the terminal 10 aa may transmit the IP address of the terminal10 aa to the management system 50 (S62). Alternatively, the terminal IPaddress may be previously registered in the terminal management table inassociation with the terminal ID.

The transmitter/receiver 51 of the management system 50 transmitsauthentication result information indicating an authentication resultobtained by the memory control 59 to the starting terminal 10 aa whichhas sent the above-mentioned login request, via the communicationnetwork 2 (S65). In the following, the case in which it has beendetermined by the memory control 59 that the terminal 10 aa is aterminal that has a legitimate use authority will be described asfollows.

As the terminal 10 aa, which is the starting terminal, receives theauthentication result information indicating that the terminal 10 aa isan authenticated terminal at the transmitter/receiver 11, thetransmitter/receiver 11 of the terminal 10 aa transmits contact listrequest information that requests for contact list to the managementsystem 50 through the communication network 2 (S66). Thetransmitter/receiver 51 of the management system 50 receives the contactlist request information.

The memory control 59 of the management system 50 searches the contactlist management table (FIG. 11) using the terminal ID of the startingterminal 10 aa which has sent the login request as a search key, toextract the terminal ID of a candidate counterpart terminal that cancommunicate with the starting terminal 10 aa. The memory control 59 ofthe management system 50 further reads out the terminal name associatedwith the extracted terminal ID from the terminal management table (FIG.10) (S67). In this example, the terminal IDs (such as “01ab” . . . ) andthe terminal names (such as “Japan Osaka Office AB Terminal”) of theterminals 10 ab . . . , as a counterpart terminal for the startingterminal 10 aa, are extracted from the contact list management table(FIG. 11) and the terminal management table (FIG. 10).

The memory control 59 of the communication management system 50 readscontact list frame data, and icon data reflecting the operating state ofeach candidate counterpart terminal that is read, from the memory 5000(S68). The transmitter/receiver 51 further transmits the contact listinformation to the starting terminal 10 aa (S69). The contact listinformation includes the contact list frame data, and the icon data, theterminal ID, and the terminal name of each candidate counterpartterminal 10. The starting terminal 10 aa, which receives the contactlist information at the transmitter/receiver 11, stores the receivedcontact list information in the memory 1000 via the memory control 19(S70).

As described above, in this embodiment, instead of managing contact listinformation at each communication terminal, the management system 50centrally manages contact list information for all of the terminals 10.In this way, even when a communication terminal is newly added or theexisting communication terminal is replaced with a different type ofcommunication terminal, or even when contact list frame is changed, thecommunication management system 50 can centrally reflect such changewithout requiring each communication terminal to reflect such change.

Still referring to FIG. 16, the memory control 59 of the managementsystem 50 searches the terminal management table (FIG. 10) using theextracted terminal IDs (10 ab . . . ) of the candidate counterpartterminals (10 ab . . . ), as search keys, to obtain the operating statesof the candidate counterpart terminals (S71).

Next, the transmitter/receiver 51 of the management system 50 transmitscounterpart terminal state information including the terminal IDsserving as the search keys used at S67 and the operating states of thecounterpart terminals corresponding to these terminal IDs to thestarting terminal 10 aa via the communication network 2 (S72).

The starting terminal 10 aa stores the terminal state information, whichmay be received from the management system 50 sequentially or at once,in the memory 1000 (S73). Based on the terminal state informationreceived for each candidate counterpart terminal, the starting terminal10 aa is able to know the current operating state of each candidatecounterpart terminal such as the operating state of the communicationterminal 10 ab.

Based on the contact list information and the terminal state informationstored in the memory 1000, the display control 14 of the startingterminal 10 aa generates a contact list that reflects the currentoperating state of each candidate counterpart terminal. The displaycontrol 14 further displays the contact list on the display 120 of FIG.2, as illustrated in FIG. 17 (S74). In FIG. 17, the icons eachreflecting the operating state of the corresponding terminal aredisplayed at left. More specifically, the icons in FIG. 17 indicate theoperating states of “online (communication OK)”, “offline”, “online(communication OK)”, and “online (communicating), from the top to thebottom.

The memory control 59 of the management system 50 further searches thecontact list management table of FIG. 11 using the terminal ID “01aa” ofthe starting terminal 10 aa which has sent the login request as a searchkey, to extract the terminal 1D of another starting terminal thatregisters the terminal ID “01aa” of the starting terminal 10 aa as acandidate counterpart terminal (S75). In the candidate list managementtable illustrated in FIG. 11, the terminal IDs of other startingterminals that are extracted are “01ab”, “01ba”, and “07db”.

Next, the memory control 59 of the management system 50 searches thecontact list management table (FIG. 10) using the terminal ID of thestarting terminal 10 aa which has sent the login request as a searchkey, and obtains the operating state of the starting terminal 10 aa(S76).

The transmitter/receiver 51 transmits counterpart terminal stateinformation including the terminal ID “01aa” and the operating state“Online (Communication OK)” of the starting terminal 10 aa, obtained atS76, to terminals (10 ab and 70 db) whose operating states are “Online(Communication OK)” in the terminal management table (FIG. 10), amongthe terminals (10 ab, 10 ba, and 70 db) having the terminal IDs (“01ab”,“01ba”, and “07db”) extracted at S75 (S77). When transmitting thecounterpart terminal state information to the terminals (10 ab and 70db), the transmitter/receiver 51 refers to the IP addresses of theterminals, which are managed in the terminal management tableillustrated in FIG. 10, using the terminal IDs (“01 ab” and “07db”).Accordingly, the terminal ID “01aa” and the operating state “online” ofthe starting terminal (terminal 10 aa) which has sent the login requestcan be transmitted to other counterpart terminals (terminals 10 ab and70 db) that can communicate with the starting terminal (terminal 10 aa).Accordingly, the candidate counterpart terminal 10 (such as the terminal10 ab) is able to display the contact list with the operating stateinformation as illustrated in FIG. 16 (S78).

Referring to FIGS. 18 and 19, operation of obtaining terminalidentification information for identifying the communication terminal 70db from the mobile terminal 90 a, by the communication terminal 10, isdescribed according to an embodiment of the present invention. FIG. 18is a data sequence diagram illustrating operation of obtaining theterminal identification information. FIG. 19 is a flowchart illustratingoperation of identifying a communication destination for thecommunication terminal 10.

The user X at the site A brings the mobile terminal 90 a close to thecommunication terminal 10 aa, while the contact list of FIG. 17 is beingdisplayed on the display 120 of the communication terminal 10 aa. Thedeterminer 15 of the communication terminal 10 aa determines whether anydevice is detected near the communication terminal 10 aa. The followingassumes the case in which the user X brings the mobile terminal 90 aclose to the communication terminal 10 aa such that the mobile terminal90 a is detected.

The obtainer/provider 98 a of the communication terminal 10 aa transmitsa request for reading the terminal identification information to themobile terminal 90 a via near-distance wireless communication (S82). Thememory control 99 a of the mobile terminal 90 a reads out the terminalidentification information (in this example, the terminal ID) of thecommunication terminal 70 db from the memory 9000 a (S83).

Next, the obtainer/provider 98 a of the mobile terminal 90 a transmitsthe terminal ID, which is read, to the communication terminal 10 aa vianear-distance wireless communication (S84). The obtainer/provider 18 ofthe communication terminal 10 aa receives the terminal ID of thecommunication terminal 70 db from the mobile terminal 90 a. The memorycontrol 19 stores the terminal ID in the memory 1000 (S85).

The communication terminal 10 aa identifies a destination ofcommunication using the terminal (terminal ID) that is received at S85(S86). Referring to FIG. 19, S86 of identifying the destination isdescribed.

As illustrated in FIG. 19, the selector 16 of the communication terminal10 aa selects communication application to be activated, based on thereceived terminal identification information (S86-1). In this example,since the terminal ID is received, the selector 16 selects thecommunication application A1 corresponding to the terminal ID to startcommunication. The activator 17 activates the communication applicationA1 (S86-2).

The memory control 99 a searches the contact list information stored inthe memory 1000 at S70 using the terminal ID received at S84 as a searchkey (S86-3). Based on the search, the determiner 95 a determines whetherthe received terminal ID matches any one of the terminal IDs of thecandidate counterpart terminals (S86-4). When it is determined that thereceived terminal ID matches any one of the terminal IDs of thecandidate counterpart terminals as indicated by the contact listinformation (“YES” at S86-4), the operation proceeds to S121 of FIG. 22.When it is determined that the received terminal ID does not match anyone of the terminal IDs in the candidate counterpart terminals asindicated by the contact list information (“NO” at S86-4), the operationproceeds to S101 of FIG. 22.

Referring to FIGS. 20 and 21, operation of adding a candidatecounterpart terminal to the contact list is described according to theembodiment of the present invention. FIG. 20 is a data sequence diagramillustrating operation of adding a candidate counterpart terminal to thecontact list. FIG. 21 is an example screen for requesting approval toadd a candidate counterpart terminal to the contact list.

In this example, it is assumed that the terminal 10 aa requests thecommunication terminal 70 db to approve to add the communicationterminal 70 db to a contact list of the communication terminal 10 aa.Here, the communication terminal 10 aa corresponds to the request senderterminal, and the communication terminal 70 db corresponds to therequest destination terminal.

The transmitter/receiver 11 of the request sender terminal 10 aatransmits a request for adding the counterpart terminal (additionrequest) to the communication management system 50 through thecommunication network 2 (S101). The addition request includes theterminal ID “01aa” of the request sender terminal 10 aa, and theterminal ID “07db” of the request destination terminal 70 db. Thetransmitter/receiver 51 of the management system 50 receives theaddition request.

The memory control 59 of the communication management system 50 stores,for a new entry of the addition request management table (FIG. 12), theterminal ID “01aa” of the request sender terminal 10 aa in a requestsender terminal ID field, and the terminal ID “07db” of the requestdestination terminal 70 db in a request destination terminal ID field(S102).

The determiner 52 searches the terminal management table (FIG. 10) usingthe terminal ID “07db” of the request destination terminal 70 db toobtain the operating state of the communication terminal 70 db (S103).When the determiner 52 determines that the request destination terminal70 db is online but has not started communication, at S104, thetransmitter/receiver 51 transmits an addition approval request forrequesting approval to add, to the request destination terminal 70 db(S104). The addition approval request includes the terminal ID “01aa” ofthe request 10 aa. The transmitter/receiver 71 of the requestdestination terminal 70 db receives the addition approval request.

Next, the display control 74 of the request destination terminal 70 dbcauses the display 753 to display an addition request response screen asillustrated in FIG. 20 (S105).

The transmitter/receiver 71 of the request destination terminal 70 dbtransmits a response to the addition approval request, which indicatesapproval, rejection, or holding, to the communication management system50 (S106). The user D, at the site D, selects “YES” key on the screen toapprove the request for adding the terminal 70 db to the contact list.The user D selects “NO” key on the screen to reject the request foradding the terminal 70 db to the contact list. The user D selects“CANCEL” key on the screen to postpone a response to the request foradding the terminal 70 db to the contact list. The transmitter/receiver51 of the management system 50 receives the response to the additionapproval request. The example case in which the response indicatesapproval to add the request destination terminal 70 db to the contactlist for the terminal 10 aa.

The memory control 59 of the management system 50 registers the terminalID “07db” of the request destination terminal 70 db, in a record(contact list) for the request sender terminal 10 aa in the contact listmanagement table (FIG. 11) (S107).

If the response indicates to reject the request for adding the terminal70 db, at S107, the memory control 59 deletes the record created for therequest sender terminal 10 aa, in the addition request management table(FIG. 12). If the response indicates to hold the response, at S107, thememory control 59 just waits for response, while not performing anythingwith respect to the contact list management table or the additionrequest management table.

The memory control 59 searches the terminal management table (FIG. 10)using the terminal ID “01aa” of the request sender terminal 10 aa andthe terminal ID “07db” of the request destination terminal 70 db, toobtain the terminal name and the operating state for each of the requestsender terminal and the request destination terminal (S108). Thetransmitter/receiver 51 transmits a notification indicating completionof addition to the contact list to each of the request sender terminal10 aa and the request destination terminal 70 db (S109-1, 2). Thenotification to be transmitted to the request sender terminal 10 aaincludes a message indicating completion of addition, and variousinformation (terminal ID, terminal name, and operating state) of therequest destination terminal 70 db. That is, only information regardingthe communication terminal 70 db that is newly added is transmitted tothe communication terminal 10 aa. The notification to be transmitted tothe request destination terminal 70 db includes a message indicatingcompletion of addition, and various information (terminal ID, terminalname, and operating state) of the request sender terminal 10 aa.

The display control 14 of the request sender terminal 10 aa causes thedisplay 120 to display a screen indicating completion of addition(S110-1). The display control 74 of the request destination terminal 70db causes the display 753 to display a screen indicating completion ofaddition (S110-2). After S101-1 and S101-2, the memory control 59 of thecommunication management system 50 deletes the record created for therequest sender terminal 10 aa and the request destination terminal 70db, in the addition request management table (FIG. 12) (S111). Theoperation then automatically proceeds to S121 of FIG. 22.

Referring to FIG. 22, operation of preparing for transmission of imagedata and audio data, performed by the communication system 1, isdescribed according to an embodiment of the present invention. FIG. 22is a data sequence diagram illustrating operation of preparing fortransmission of image data and audio data.

When it is determined that the contact list information includes thereceived terminal ID (“YES” at S86-4 of FIG. 19), the user X does nothave to select the communication terminal 70 db, from the contact listof FIG. 17, as a counterpart terminal to start communication. In suchcase, the communication terminal 10 aa automatically transmits acommunication start request for starting communication with thecounterpart terminal 70 db, to the communication management system 50.Specifically, the transmitter/receiver 11 transmits a communicationstart request to the communication management system 50 through thecommunication network 2 (S121). The communication start request includesthe terminal ID “01aa” of the starting terminal 10 aa, and the terminalID “07db” of the counterpart terminal 70 db. The transmitter/receiver 51of the management system 50 receives the communication start request.

On the basis of the terminal ID “01aa” of the starting terminal 10 aaand the terminal ID (“07db”) of the counterpart terminal 70 db, whichare included in the communication start request, the memory control 59of the communication management system 50 changes the operating statefield of each of records including the above-mentioned terminal IDs“01aa” and “07db” to “communicating” in the terminal management table(FIG. 10) (S122). In this state, although the starting terminal 10 aaand the counterpart terminal 70 db have not started communicating, theseterminals enter a communicating state, and, if another terminal 10 triesto communicate with the starting terminal 10 aa or the counterpartterminal 70 db, a notification sound or display that indicates that theterminal is communicating is output.

Next, the memory control 59 of the communication management system 50searches the terminal management table (FIG. 10) using the terminal ID“01aa” of the starting terminal 10 aa and the terminal ID “07db” of thecounterpart terminal 70 db, received at S121, as search keys, to readcorresponding IP addresses (S123).

The transmitter/receiver 51 of the management system 50 transmits thecommunication start request to the IP address of the counterpartterminal 70 db, which is read at S123 (S124). The communication startrequest includes the terminal IDs “01aa” and “07db”, as received atS121. The transmitter/receiver 71 of the counterpart terminal 70 dbreceives the communication start request.

The transmitter/receiver 71 of the counterpart terminal 70 db transmitsa response to the communication start request, to the communicationmanagement system 50 (S125). The transmitter/receiver 51 of themanagement system 50 receives the response to the communication startrequest. The communication start request indicates whether to accept orreject communication. The example case of accepting the communicationstart request is described.

The transmitter/receiver 51 of the management system 50 transmits arelay start request indicating a request for starting relaying to therelay device 30 (S126). The relay start request includes the IPaddresses of the starting terminal 10 aa and the counterpart terminal 70db read at S123. The transmitter/receiver 31 of the relay device 30receives the relay start request.

The transmitter/receiver 51 of the management system 50 transmits theresponse to the communication start request, which is received at S125,to the starting terminal 10 aa (S127). As described above, in thisexample, the transmitter/receiver 11 of the starting terminal 10 aareceives the response accepting the communication start request.

As described above, the starting terminal 10 aa and the counterpartterminal 70 db establish an image data/audio data communication sessionvia the relay device 30 (S128-1, 2) to start videoconference.

As described above, according to some embodiments of the presentinvention, at the site D, the mobile terminal 90 a operated by the userX obtains terminal identification information of the communicationterminal 70, from the communication terminal 70. The mobile terminal 90a, after moving to the site A, provides the obtained terminalidentification information to the communication terminal 10. Thecommunication terminal 10, which obtains the identification informationof the counterpart communication terminal 70, starts communication withthe counterpart communication terminal 70.

This simplifies a process of preparing to start communication, thusreducing the time for preparing to start communication between thecommunication terminal 10 and the communication terminal 70.

More specifically, based on the terminal identification information ofthe counterpart communication terminal 70, the communication terminal 10automatically identifies a communication destination of thecommunication terminal 10, using the obtained terminal identificationinformation. This eliminates a need for manually selecting a counterpartcommunication terminal from among a plurality of candidate counterpartcommunication terminals in the contact list.

Further, even when the communication terminal 70 as the communicationdestination is not registered in the contact list for the communicationterminal 10 as the starting terminal, the communication terminal 10automatically sends a request for approval to add the communicationterminal 70 to the contact list of the communication terminal 10. Basedon a response indicating approval, the communication terminal 10 addsthe communication terminal 70 to the contact list, and startscommunication with the communication terminal 70. This furthereliminates a need for entering a request for addition approval, ormanually adding the communication terminal 70 to the contact list.

Further, even when a plurality of types of communication application isinstalled on the respective communication terminals, the communicationterminal 10 automatically selects communication application to be usedfor communicating with the counterpart communication terminal 70, basedon a type of terminal identification information of the counterpartcommunication terminal 70. Further, the terminal identificationinformation, which is used to select specific communication application,does not have to be manually entered. This further simplifies theprocess to start communication with the counterpart communicationterminal.

In the above-described embodiment, the example case in which the mobileterminal 90 a moves from the site D to the site A, along with the userX. However, the above-described embodiment is applicable to the othersituation. In one example, the mobile terminal 90 operated by the user Ymay move from the site D to the site A, along with the user Y. Inanother example, the mobile terminal 90 operated by the user X may movefrom the site A to the site D, after the mobile terminal 90 obtains theterminal identification information of the communication terminal 10 atthe site A.

In the above-described embodiment, the communication terminal (10, 70)provides the terminal identification information to the mobile terminal90 by near-distance wireless communication, the communication terminalmay provide using any other communication network including a wirednetwork such as by a USB cable. In addition, although the case of avideoconference terminal has been described as an example of acommunication terminal in the above-described embodiment, the embodimentis not limited to this case, and the communication system 1 may be aphone system such as an IP phone system or an Internet phone system. Inaddition, a smart phone, a smart watch, a mobile phone, a car navigationterminal, a wearable computer, a monitoring camera, a digital cameracommunicable using WiFi, any communication device (a projector, a gamemachine), a digital signage, or industrial equipment with acommunication function may be used. A wearable computer includes a watchand a head-mounted display. Industrial equipment includes officeequipment such as a multifunction peripheral (MFP)/printer/product,medical equipment such as an endoscope, a Computed Tomography (CT) scan,and radiotherapy equipment, and agricultural equipment such as acultivator.

In addition, although image data and audio data are described asexamples of content data in the above-described embodiment, the contentdata is not limited to these items of data, and the content data may betouch data. In this case, a feeling obtained by a user's contact at oneterminal side is transmitted to the other terminal side. Further, thecontent data may be smell data. In this case, a smell at one terminalside is transmitted to the other terminal side. In addition, the contentdata may be at least one of image data, audio data, touch data, andsmell data.

In addition, although the case in which a videoconference is held by thecommunication system 1 has been described in the above-describedembodiment, the embodiment is not limited to this case. Thecommunication system 1 may be used in meetings, general conversationbetween family members or friends, or one-way presentation ofinformation.

In case the communication terminal 70 is implemented as the electronicwhiteboard, because of its relatively large size, the functions of thecommunication management system 50 and/or the relay device 30 may beincorporated in the communication terminal 70. In such case, theterminal at the site A and the terminal at the site D can becommunicated via the Intranet, configuring the on-premises system. Thisimproves a level of security.

In the above-described embodiment, the recording request or the readingrequest is transmitted or received by near-distance wirelesscommunication. Alternatively, such request may be transmitted orreceived by ultrasonic communication. In alternative to transmitting therecording request, the communication terminal 10 or 70 may display animage encoded with the terminal ID (for example, in the form of abi-dimensional bar code or a QR code). The mobile terminal 90 a maycapture the image with the camera to obtain the terminal ID of thecommunication terminal 10 or 70, and store the obtained the terminal IDin its memory. In alternative to transmitting the reading request, thecommunication terminal 10 or 70 may display an image encoded with theterminal ID (for example, in the form of a bi-dimensional bar code or aQR code). The mobile terminal 90 a may capture the image with the camerato obtain the terminal ID of the communication terminal 10 or 70.

Numerous additional modifications and variations are possible in lightof the above teachings. It is therefore to be understood that within thescope of the appended claims, the disclosure of the present inventionmay be practiced otherwise than as specifically described herein. Forexample, elements and/or features of different illustrative embodimentsmay be combined with each other and/or substituted for each other withinthe scope of this disclosure and appended claims.

Each of the functions of the described embodiments may be implemented byone or more processing circuits or circuitry. Processing circuitryincludes a programmed processor, as a processor includes circuitry. Aprocessing circuit also includes devices such as an application specificintegrated circuit (ASIC), digital signal processor (DSP), fieldprogrammable gate array (FPGA), and conventional circuit componentsarranged to perform the recited functions.

1. A communication terminal configured to communicate with a counterpartcommunication terminal, the communication terminal comprising: areceiver to receive, from a mobile terminal, first terminalidentification information for identifying a first communicationterminal that is located remotely from the communication terminal, themobile terminal being a mobile terminal that has obtained the firstterminal identification information from the first communicationterminal; and circuitry to determine the first communication terminalidentified with the first terminal identification information as acommunication destination, and start communicating with the firstcommunication terminal.
 2. The communication terminal of claim 1,further comprising: a transmitter to transmit a request for startingcommunication with the first communication terminal, wherein thereceiver receives the first terminal identification information from themobile terminal by near-distance wireless communication, and thetransmitter transmits the request to the first communication terminalvia a network.
 3. The communication terminal of claim 2, wherein thenear-distance wireless communication includes one of near-fieldcommunication (NFC) and Bluetooth.
 4. The communication terminal ofclaim 1, further comprising: a memory to store, for each one of one ormore candidate counterpart communication terminals capable ofcommunicating with the communication terminal, terminal identificationinformation identifying the respective communication terminal, whereinthe circuitry further determines whether the first terminalidentification information matches any one of the terminalidentification information stored in the memory, and startscommunicating with the first communication terminal based on adetermination indicating that the first terminal identificationinformation matches the terminal identification information stored inthe memory.
 5. The communication terminal of claim 4, wherein, based ona determination indicating that the first terminal identificationinformation does not match the terminal identification informationstored in the memory, the circuitry transmits a request for adding thefirst communication terminal as a candidate counterpart communicationterminal for the communication terminal, to the first communicationterminal via a communication management system.
 6. The communicationterminal of claim 1, wherein the communication terminal is installedwith a plurality of types of communication application, and thecircuitry selects one of the plurality of types of communicationapplication according to a description format of the first terminalidentification information, and starts communicating with the firstcommunication terminal using the selected communication application. 7.The communication terminal of claim 6, wherein the description format ofthe first terminal identification information indicates whether thefirst terminal identification information is one of a terminalidentifier identifying the first communication terminal, an IP addressto be used for accessing the first communication terminal, and an emailaddress assigned to the first communication terminal.
 8. A communicationsystem, comprising: a first communication terminal including: a memoryto store first terminal identification information identifying the firstcommunication terminal; and first circuitry to provide the firstterminal identification information read out from the memory to a mobileterminal; and a second communication terminal including: secondcircuitry to obtain the first terminal identification information fromthe mobile terminal; and a transmitter to transmit a request forstarting communication with the first communication terminal toestablish a communication session with the first communication terminal.9. The communication system of claim 8, wherein the first communicationterminal and the second communication terminal is one of avideoconference terminal, electronic whiteboard, projector, IPtelephone, Internet telephone, car navigation terminal, monitoringcamera, printer, facsimile, multifunctional peripheral (MFP), electronicendoscope, and radiotherapy equipment.
 10. The communication system ofclaim 8, further comprising: a communication management system thatcontrols communication between the communication terminal and the firstcommunication terminal, wherein the communication terminal transmits therequest for starting communication to the communication managementsystem.
 11. The communication system of claim 8, further comprising: arelay device to relay content data between the communication terminaland the first communication terminal.
 12. The communication system ofclaim 8, further comprising: the mobile terminal being one of a smartphone, mobile phone, digital camera, mobile game machine, IC card, smartwatch, and head-mounted display.
 13. A method of communicating with acounterpart communication terminal, the method comprising: receiving,from a mobile terminal, first terminal identification information foridentifying a first communication terminal that is located remotely fromthe communication terminal, the mobile terminal being a mobile terminalthat has obtained the first terminal identification information from thefirst communication terminal; determining the first communicationterminal identified with the first terminal identification informationas a communication destination; and starting communicating with thefirst communication terminal.
 14. The method of claim 13, furthercomprising: transmitting a request for starting communication with thefirst communication terminal, wherein the receiving receives the firstterminal identification information from the mobile terminal bynear-distance wireless communication, and the transmitting transmits therequest to the first communication terminal via a network.